Immersion cooling is a technology used to cool electronic processing equipment, particularly for high speed and high data capacity processing equipment, where conventional air cooling has been found inadequate. Immersion cooling involves immersing the equipment (e.g. electronic data processing modules) in a tank containing a liquid. Convection and evaporation of the liquid can provide very high cooling rates to keep the modules within their normal operating temperature range. Water is not an ideal liquid to use for these applications because (a) it is electrically conductive meaning that some type of insulation would need to be used between the water and the electronics, thereby reducing the cooling effectiveness, and (b) because water evaporates at too high a temperature. Instead more effective, non-conductive cooling fluids that evaporate at lower temperatures have been developed. An example of this is the NOVEC™ 649 engineered fluid manufactured by 3M™ of St. Paul, Minn. However, even with the use of these fluids problems can arise if moisture gets into the liquid. Even small amounts of water can cause shorting of electrical connections in the electronic equipment. Another problem is that because the specialized cooling liquids are expensive, it is important to retain all, or as much as possible of the material in the vessel and to minimize any loss as a result of the evaporation.
Various modifications and improvements in immersion cooling are presented below.